At present, secrecy performance of commonly used mechanical combination locks is weak, and it is troublesome during the code changing.
For example, the lock needs to be disassembled for code changing while changing a single code key in conventional code changing manner, therefore it is very troublesome. Especially with regard to the code changing mechanism of the mechanical combination lock with vast code information, the structure is more complex, so it is easy to break down and service lift is not long. Moreover, capability of preventing code cracking of conventional mechanical combination lock is not robust enough, and it is easily cracked by a thief.